Effects of methylcellulose,xanthan gum and carboxymethylcellulose on thermal properties of batter systems formulated with different flour combinations

The functionalities of hydrocolloid–flour mixtures in terms of the thermal properties of their resulting batter systems were investigated, and the effects of different thermal processes such as cooking–freezing–thawing (CFT) and freezing–cooking (FC) on thermal properties of the various batter systems were determined in this study. Differential scanning calorimetry (DSC) was used to determine thermal property parameters including gelatinization temperature (T_G), total enthalpies of gelatinization (ΔH_G), glass transition temperature (T_g), melting peak temperature (T_m), and total melting enthalpies (ΔH_m). The different thermal processes did not significantly affect either T_G or ΔH_G of batter systems, but they influenced the glass transition behavior and the ΔH_m of batter systems. The thermal processes also showed different effects on the batter systems containing different hydrocolloids such as methylcellulose (MC), carboxymethylcellulose (CMC), and xanthan gum (XG). The hydrocolloids shifted T_G upwards, depressed T_g, and increased T_m of batters. The effect of these hydrocolloids on glass transition temperature was more pronounced in raw samples (FC process) than in cooked samples and increased with increasing levels of CMC and MC used in the formulations. Batters with MC showed increased ΔH_m for all the thermal processes. CMC only showed significant effect on ΔH_m for cooked samples (CFT process). MC and CMC showed more pronounced effects on T_g for raw uncooked rice- and corn flour-based batters than on raw uncooked wheat flour-based batters. However, this special effect was not obvious in the batters containing 0.2% XG.